Serialize Strings, ints and floats to character arrays for networking WITHOUT LIBRARIES

Question

I want to transmit data over the network, but I don\'t want to use any foreign libraries (Standard C/C++ is ok).

for example:

unsigned int x = 123;
c         


        

Answer 1

Something like the code below would do it. Watch out for problems where sizeof(unsigned int) is different on different systems, those will get you. For things like this you're better off using types with well-defined sizes, like int32_t. Anyway...

unsigned int x = 123;
char y[3] = {'h', 'i', '\0'};
float z = 1.23f;

// The buffer we will be writing bytes into
unsigned char outBuf[sizeof(x)+sizeof(y)+sizeof(z)];

// A pointer we will advance whenever we write data
unsigned char * p = outBuf;

// Serialize "x" into outBuf
unsigned int32_t neX = htonl(x);
memcpy(p, &neX, sizeof(neX));
p += sizeof(neX);

// Serialize "y" into outBuf
memcpy(p, y, sizeof(y));
p += sizeof(y);

// Serialize "z" into outBuf
int32_t neZ = htonl(*(reinterpret_cast(&z)));
memcpy(p, &neZ, sizeof(neZ));
p += sizeof(neZ);

int resultCode = send(mySocket, outBuf, p-outBuf, 0);
[...]

... and of course the receiving code would do something similar, except in reverse.